Light and chime control system

ABSTRACT

A daylight sensor and a headlight sensor are connected in a variable voltage divider. When darkness turns the daylight sensor off and headlights turn a sensor on, a potential is provided to a voltage gate which is sufficient to break down a zener diode and gate current to a timer circuit. A diode in the voltage gate prevents reverse flow of current from a timer. A timer circuit contains a capacitor and resistor which discharges the capacitor. When the voltage is gated to the timer circuit and during the time that capacitor maintains a sufficient potential, a light switch is held on. A triac in the light switch control the lights. Approximately 3 seconds after the capacitor in the timer is charged to its potential, a transistor is switched on, placing a ground potential to the midpoint of the voltage divider to cut off the gate voltage. A chime operator is activated by sampling the potential from the variable voltage divider to slowly ring a door chime as an automobile is sensed. House and garage lights are lighted automatically a short time after a doorbell is rung at night to suggest a human response to the doorbell.

United States Patent u m1 3,886,352

Lai May 27, 1975 LIGHT AND CHIME CONTROL SYSTEM [57] ABSTRACT [76]Inventor: Thomas Laii 38 Niolopa A daylight sensor and a headlightsensor are con- Place' Honolulu Hawa" 96800 nected in a variable voltagedivider. When darkness [22] Fiied: Oct 25 1973 turns the daylight sensoroff and headlights turn a sensor on, a potential is provided to avoltage gate which [2 l 1 APPL Nod 409662 is sufficient to break down azener diode and gate cur- Relfled s Application Data rent to a timercircuit. A diode in the voltage gate pre- [63] Continuation-impart ofSer. No. 242,351, April 10, Vents reverse now of from a 1972, Pat. No.3,790,848. A timer circuit contains a capacitor and resistor whichdischarges the capacitor. When the voltage is gated to [52] US. Cl250/215; 3l5/360; 340/31 R; the timer circuit and during the time thatcapacitor 340/51; 340/392 maintains a sufficient potential, a lightswitch is held [51] Int. Cl G08g l/14; GlOk 3/00; H05b 4l/36 on. A triacin the light switch control the lights. [58] Field of Search 250/2l5,206; 340/3! R, Approximately 3 Seconds after the capacitor in the 340/51392; 315/360 136 timer is charged to its potential, a transistor isswitched on, placing a ground potential to the References cued midpointof the voltage divider to cut off the gate UNITED STATES PATENTSvoltage. 666,737 l/l90l Coleman 250/206X A hi erator is activated bysampling the 774,457 3/1930 Singletonm 340/51 potential from thevariable voltage divider to slowly 2,360,885 10/1944 Metcalf 340/5 ringa door chime as an automobile is sensed. House 3,530,432 9/1970 Pope340/3l and g g lights are lighted automatically a short time after adoorbell is rung at night to suggest a human response to the doorbell.

Primary Examiner-James W. Lawrence Assistant Examiner-T. N. GrigsbyAttorney, Agent, or FirmJames C. Wray 9 Claims, 6 Drawing Figures DOORBELL SWITCH SHEET IUFE/w 1mm UOOQ OP 1 LIGHT AND CHIME CONTROL SYSTEMThis application is a continuation-in-part of patent application Ser.No. 242,351 now US. Pat. No. 3,790,848 filed Apr. 10, 1972 by Thomas K.Y. Lai for Automatic Light Control System.

BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION The automatic lightcontrol system is designed to provide home owner with safety, convenientand security within a garage or passageways or residences with minimuminvestment lasting a lifetime.

This solid state device is used for controlling and providing temporarylighting in darkened areas usually outside a house or apartment. Lightscontrolled by this system are usually those lights within a garage,those within a passageway, or those between a parking space andresidence, or those placed exteriorly near the front door or insidelights.

The system is designed to operate in any house, garage or carport.Pneumatic switches are provided for homes with driveways, to turn onlights to ring door chimes when vehicles enter the area.

The operation of this system is automatically turned off during thedaylight hours.

Parameters of system operation are described as follows:

Power Requirement: 117 volts AC, 60 Hertz, Fuse for half amps.

Circuit Power Supply: Regulated 11.8 volts DC. Circuit DC Current Drain:

Daylight Hours approximately 30 MA.

Night Hours STAND BY less than MA., OPER- ATING approximately 60 MA.

Load: 450 watts maximum, incondescent lamps.

Time Delay: 4 minutes and 9 minutes.

Condition Held System inoperative: Daylight hours hazy, overcast, dawnto dusk.

Light Starting Requirement:

1. 470 ohms control element at voltage divider circuit between midpointand positive line.

2. three second of exposure of I00 foot-candle illumination on interiorphotocell.

Self Adjust Sensor Circuit:

Interior photocell PCl becomes de-sensitized to 60 foot-candleillumination in three seconds after the light is started. The interiorphotocell automatically restores to maximum sensitivity when the area isdarkened.

The embodiments of this device take two forms, permanent installation orplug-in types. The system comprises electronic circuitry which isenclosed in the main chassis box with two terminal blocks. One terminalblock is a low voltage block to which the remote switching or startingelements are connected, for example, a push-to-light switch near adoorway for starting a system as one leaves the house. A headlightreceiving photocell is employed to switch on lights as the automobileapproachs the area. A pneumatic switch may be substituted for thephotocell sensor in some cases, such as in drive-through carports whereno wall is available for mounting of an interior photocell. A daylightsensor photocell is mounted on an exterior of a building to preventionoperation of the system during the daylight hours. A chime operator isconnected to the system to ring the door chime.

A daylight sensor and a headlight sensor are connected in a variablevoltage divider. When darkness turns the daylight sensor off andheadlights turn a sensor on, a potential is provided to a voltage gatewhich is sufficient to break down a zener diode and gate current to atimer circuit. A diode in the voltage gate prevents reverse flow ofcurrent from a timer.

A timer circuit contains a capacitor and resistor which discharges thecapacitor. When the voltage is gated to the timer circuit and during thetime that capacitor maintains a sufficient potential, a light switch isheld on. A triac in the light switch controls the lights.

Approximately 3 seconds after the capacitor in the timer is charged toits potential, a transistor is switched on, placing a ground potentialto the midpoint of the voltage divider to cut off the gate voltage.

A chime operator is activated by sampling the potential from thevariable voltage divider to slowly ring a door chime as an automobile issensed. House and garage lights are lighted automatically a short timeafter a doorbell is rung at night to suggest a human response to thedoorbell.

A power supply transmits power to the light switch and also providesll.8 volt DC to the circuit.

DETAILED DESCRIPTION OF THE DRAWINGS Throughout the drawings, likeelements are referred to by like numerals.

FIG. 1 generally indicates the light control system of a preferredembodiment of the present invention. Electric lights 2 represent alighting circuit which is controlled by the automatic device of thepresent invention. Plug 4 is representative of a connection for a powersource. Box 6 contains the electronic circuits of the present inventionand terminal boards.

Photocell 8 is mounted on an exterior of a building, for example, agarage to prevent operation of the system during daylight hours in oneembodiment. Photocells 10 are mounted within a garage to detectheadlights of cars for starting the system when a car is parked in agarage. In a two-car garage, photocells 10 may be mounted to detectheadlights from either car. Photocells 10 may be used with adjustablecircuits to detect back up lights when automobiles are backed into agarage.

In some cases, such as in drive-through carports, no wall is availablefor mounting of an interior photocell. A pneumatic switch may besubstituted for photocells 10. A closed air hose supplies a pulse of airto a switch as an automobile crosses the hose. It is convenient to mounta push button starter adjacent a pedestrian entry to the garage. Wheremore than one entry to a garage is commonly used in darkness hours, twoor more push buttons may be connected in parallel.

As shown schematically in FIG. 2, exterior photocell 8 and interiorphotocell 10 are connected in a variable voltage divider 20. Whendarkness turns photocell 8 off, and headlights turn photocell 10 on, apotential is provided to voltage gate 22 which is sufficient tobreakdown device 24 and gate current to timer circuit 30. Unidirectionaldevice 26 in gate 22 prevents reverse flow of current from timer 30.

Timer circuit 30 contains a capacitor 32 and a resistance 34 whichdischarges the capacitor. When the potential is gated to the timercircuit 30, and during the time that capacitor 32 maintains a sufficientpotential, light switch 36 is held on. Triac 38 is schematically shownwithin the light switch 36 for controlling lamp 2.

Power supply 40 receives power from source 4, transmits the power to thelight switch 36. and reduces and rectifies current which it supplies tothe variable voltage divider, the gate and the timer circuit.

A three seconds cut off 50 with a transistor 52 is connected to gate 22and voltage divider 20 to desensitize the interior photocell 8 toillumination after the system has been on for 3 seconds.

In FIG. 3 a low voltage terminal board generally indicated by TH] hasconnections A through G. which are found also in the upper part of thefigure. High voltage terminal board TB2 has connections A, B and C whichalso are shown in the upper part of the drawing as, for example, TBZ-A.Terminals A and B on the high voltage board are connected to lamps 2,and terminals B and C are connected to a voltage source which is shownas a plug 4. ln systems which are intended for use in new constructions,lamps 2 generally indicate the basic garage lights, lights within ahouse and lights near doorsv Source 4 is wired directly to the roughedin electrical wiring. ln add on systems a plug 4 and power lines aresupplied. Lamps 2 may be the existing lamps. or lamps may be providedwith a kit.

()n the low voltage terminal board TBl, contacts A and B receive pushbutton 16. Terminals C and D receive internal photocell or a roll overswitch, or both may be connected in parallel to TBl terminals C and D.Terminals E and F receive low voltage wiring from the external photocell8. Terminal G is connected to ground.

Referring to the main circuit in FIG. 3, voltage is supplied at source4. A fuse 42 protects the circuit against voltage surges, which may becaused externally or by a short circuit in the system. Household currentis applied through fuse 42 to primary 44 of transformer 46. Secondary 48reduces the voltage to approximately 12 volts AC. A bridge rectifiergenerally indicated by the numeral 1 and comprising diodes 3, 5, 7 and 9changes the low AC voltage to low DC voltage. Capacitor 12 filters ACcomponents and smooths the output of the rectifier. Current limitingresistor 14 and capacitor 18 bias transistor 17 on to supply currentflow through the DC electronic components. Zener diode l9 breaks down atexcessive voltage effectively shorting capacitor 18, and turning offtransistor 17, insuring that voltage between ground 27 positive powerline 29 does not exceed a predetermined maximum.

In the variable voltage divider 20, photocells 8 and 10 may have darkresistances of about 5,000 ohms, or more, which are reduced to about 500ohms when illuminated. When photocell 8 is at a low resistance value,the voltage drops across resistances 58, photocell 8 and resistance 59cause voltage across resistance 59 suffi cient to bias transistor 54 on.Transistor 54 and resistor 53 drop connector 28 to a level sufficientlylow to prevent operation of the voltage gate 22.

[SK ohm resistor 55 is connected in parallel to the path includingresistor 53 and transistor 54in the lower portion of divider 20 so thatthe combined resistance of resistor 53 and resistor 55 is below 500 ohmswhen external photocell 8 is illuminated during daylight hours. Indaylight conditions, the potential of midpoint 28 is thus reduced towardground potential.

In the upper portion of the divider 20, light cell 10 is connected inseries with variable resistor 56, which has a capacity of about K ohms.Adjustment of resistor 56 is made to bring the mid point 28 to apotential above the breakdown voltage of the breakdown device 24 in gate22. When 12 volts are imposed across lines 27 and 29, resistor 56 may beadjusted so that when photocell 10 is illuminated by headlights duringdarkness hours, mid point 28 is brought to a potential slightly above abreakdown voltage of 6.8 volts. Correctly adjusting resistor 56according to the fixed position of photocell l0 insures correctoperation ofthe automatic system and insures against starting of thesystem by spurious illumination of photocell l0.

Photocell 10 may be replaced by an impulse switch or other suitableswitch with a series connected resistance.

For convenience, one or more push buttons 16 may be provided atentrances to a garage. Preferably the push buttons are connected inseries with a resistor 57, which may have a value of about 470 ohms.

During daylight hours, the low resistance of photocell 8 and resistor 53and the parallel resistor 55 will always keep mid point 28 below thelevel of breakdown voltage required by breakdown device 24. Whenphotocell 8 imposes its high darkness resistance, the potential of midpoint 28 is raised above the breakdown voltage by reducing resistance inphotocell 10 or by completing any of the switches.

Gate 22 contains breakdown device 24 which is preferably a zener diode.When voltage at midpoint 28 exceeds breakdown voltage, zener diode 24conducts, supplying current to capacitor 32 and to timer 30 and toelectronic switch 36. Storage capacitor 32 is charged immediately uponapplication of voltage to the timer circuit. Resistors 33 and 34discharge voltage from capacitor 32 after the applied voltage has beendiscontinued. The rate at which resistors 33 and 34 discharge voltagefrom capacitor 32 controls the period of timer 30. Discharge ofcapacitor 32 through voltage divider 20 is prevented by unidirectionalelement 26, which is a diode. Discharge of the timer through the lightswitch 36 is prevented by a high input impedence device.

As an example, the capacitor 32 may have a value of 500 microfarads.Resistor 34 may have a value of from about 150 to about 2 megaohms.

Cutoff 50 includes a transistor 52 which is biased on by capacitor 51 inabout three seconds after sufficient voltage is supplied throughresistor 33 from zener diode 24 and from capacitor 32. Transistor 52 hasan effect similar to transistor 54 in dropping the level of midpoint 28to a value insufficient to break down zener diode 24 so that lights 2may not raise the level of midpoint 28 by reducing the resistance ofphotocell l0. Cutoff 50 in effect desensitizes interior photocell 10 orrenders its effect operative to raise the level of mid point 28.Capacitor 51 maintains the on bias on transistor 52 until it dischargessufficiently through resistor 34, which is after capacitor 32 hasdischarged sufficiently to turn off swithc 36.

The function of the resistors 66, 67 and 69 and of the cascadedtransistors 68 and 68' is to forward bias the light switch 36 whilepreventing substantial discharge of capacitor 32.

When transistor 68' is biased on by voltage from the timer section 30,DC power is supplied to reed relay 63 via current limiting resistor 65.Power terminals 70 and 71 of reed relay 63 close, completing the ACcircuit to diac 60. Capacitor 61 and resistor 62 cooperate as an ACvoltage divider so that the appropriate potential is applied via diac 60to the biasing terminal of triac 38. Power terminals of triac 38complete the circuit be tween power source 4 and lights. 2.

As shown in FIG. 3, diode 64 protects the transistor 68' from suddensurges when the field collapses in the coil of relay 63. At the sametime, diode 64 keeps the relay polarized.

In summary, FIG. 3 is a schematic diagram of the main circuit. 1 17volts AC is applied across Terminal Block TBZ on Terminal B and C. Fuse42 protects the circuit against the damage whenever short circuit orvoltage surge occurs. The AC voltage is then fed to step downTransformer 46. The secondary of 48 develops a lower AC voltage, whichis rectified by a full wave bridge rectifier 3, 5, 7, and 9. Therectified DC voltage output is filtered by capacitor 12 and is coupledto the collector of transistor 17 and to the base of 17 throughresistance 14. 12 volt zener diode l9 regulates the base bias voltage,keeping the emitter voltage at constant I I8 volts.

During daylight hours, both photocells 8 and resistances drop toapproximate 450 ohms. A base bias develops across photocell 8, andresistor 59 switches on transistor 54, placing a ground potential on thecollector end of resistor 53. Resistor 53 and resistor 55 areelectrically connected in parallel, and their total resistances are low,as compared to 400 ohms of photocell l0 resistance. The voltage at themidpoint 28 is kept below the break down level of zener diode 24.

When night falls, the resistance of PCI and PC2 rise beyond 5,000 ohms.Transistor 54 cuts off the ground path of resistor 53. The midpointvoltage at 28 still is below the zener diode 24 break down level,because resistance of photocell 10 is high as compared with resistor 55.

When an automobile enters the premise, its headlights strike the sensorphotocell 10. The photocell resistance suddenly drops to 500 ohms.Voltage a midpoint 28 rises above 10 volts of which cause zener diode 24to break down. A DC current is induced through diode 26, chargingcapacitor 32. Transistor 68 is turned on by the voltage which developsacross base resistor 67 by capacitor 32. The emitter voltage acrossresistor 66 switches on transistor 68', placing a ground potential torelay 63 and energizing it.

1 17 volts AC from terminal block T132 on terminals V and C applies toresistor 62 and capacitor 61 when closing relay contacts 70 and 71. Thediac 60 which receives AC voltage from resistor 62 and capacitor 61transmits trigger pulses to the gate of triac 36. Incondescent lamp 2 isturned on by the triac.

Approximately three seconds following the sudden rise of potential incapacitor 32, a voltage is developed across resistors 33 and 34,charging capacitor 51 to a potential that sufficiently forward biasestransistor 52. Once again resistor 53 is electrically connected inparallel with resistor 55 by the collector-emitter path of transistor 52to the ground. The midpoint voltage immediately drops below the zenergated level. That cuts off the charging current to capacitor 32.Capacitor 32 begins to discharge through resistors 33 and 34. Thevoltage in 32 slowly drops to a level that turns off transistors 68 and68' and relay 63 and then the light switching circuit. The period whichtakes capacitor 32 to discharge to a cutoff level is approximately 9minutes. The time delay could be reduced to approximately 4 minutes byadding a discharge path with another resistor connected in parallel tocapacitor 32.

Terminal block TB] is used for interconnecting low voltage switchelements to the main circuit.

Terminal block TB2 provide connections between the light switch triac 36and its load. TBZ also supplies AC power to the main circuit.

When the push to light switch 16 is depressed. it applies l l.8 volts DCto 470 ohms resistor 51. The midpoint voltage at 28 rises above thegated level of zener diode 24.

A door chime operator generally referred to by the numeral is shown inFIG. 4.

Two conditions activate the door chime; when vehicle head lights aredetected by PC] photocell, and when automobile rolls over the pneumaticswitch hose.

This system utilizes the same two or more tone door chime as in a house.The vehicle entering a garage immediately activates the door chime toproduce a ding tone first and then three seconds later a dong tone. Thereason for the dragging tone is to enable homeowner to distinguish theringing sound of an incoming car and that of a person at the door.

The contacts 93 and 94 of the chime relay 92 are normally open.Referring to FIG. 4, they are connected in parallel to the door chimebutton switch 79 by a pair of wires from TB3 terminal board terminals Mand L.

When vehicle head lights are detected by photocell 10 in the mainchassis circuit in FIG. 3 the resistance of the photocell suddenlydrops, causing a positive 11.8 volts DC to appear at T8] terminal Athrough resistor 56. This voltage is transferred from terminal block TBlto chime operator box TB3 terminal 4, the voltage causes the 5.6 voltzener diode 88 to break down. Capacitor 102 picks up this positive pulseand couples it to the base of the transistor 91. This pulse energizesthe relay 92. Relay contacts 93 and 94 complete the current path of thedoor chime, which rings its first tone ding. At approximately threeseconds later, the positive voltage in terminal .1 of TB3 drops belowthe zener diode 88 break down level by the action of transistor 52 inthe main chassis. Transistor 91, losing its base bias voltage thensubsequently switches off the relay 92. The relays contacts 93 and 94are again opened to release the door chime solenoid holding current. ltsac tion rings the second tone, dong. Diode 97 is used to short out anynegative pulse at the base of transistor 91 during the capacitor 102discharge period. Resistor 103 discharges the voltage of capacitor 102.

When the light switch 16 is depressed momentarily, a positive I l.8volts DC from terminal B of TB] to terminal K of TB3 is transferred toterminal J by way of diode 87. The zener diode 88 breaks down andinduces a positive pulse to the base of transistor 91. but the pulse isgrounded by collector to emitter of transistor 98, which is turned on bythe base bias that is developed across resistors 99 and 100. Thispositive Dc volt age is made possible from TB3 terminal I. The resultsis no chime operation when the light button switch 16 is pushed.

Diode 87 is used to prevent the circuit of transistor 91 from operatingwhenever a positive DC voltage appears at terminal J of TB3.

A Light Ringer circuit is generally referred to by the numeral in FIG.5.

After a guest or burglar rings the door bell, the exterior lightsautomatically turn on approximately 40 seconds later.

As the door bell 79 is pushed, the l() or 16 volts AC from the secondarycoil of the chime transformer is applied to terminals P and Q ofterminal board T84 75 through the chime solenoid, door bell switch 79and wires 80 and 81. The diode 111 converts this AC voltage to DCvoltage across resistors 114 and 113. This DC voltage causes transistor117 to conduct. The emitter current that flows through emitter resistor118 develops a voltage across it. The AC ripple in this voltage isfiltered by capacitor 123.

When the circuit stands idle, the silicon control rectifler 116 is in anoff state. The transistors 146, 143, 137 and 138 are also in off state.The positive voltage from terminal N through resistors 131, 132 and 133charges capacitor 135 to a positive 11.5 volts.

If the door bell button is depressed momentarily, its action creates atemporary short circuit across terminals P and O. This action switchesthe transistor 117 from conduction to off and back on again. A positivepulse is generated across resistor 118 and the pulse is coupled to thegate of the SCR 116 by way of resistor 126 and capacitor 125. Thispositive pulse turns on SCR 116 which places a ground potential at thejunction of resistors 132 and 133. The positive voltage stored incapacitor 135 slowly discharges through resistor 133 and SCR 116 toground. Approximately forty seconds later, the voltage of capacitor 135drops to a level where transistors 138 and 137 begin to switch onthrough a base bias path from resistors 134 and 133 and SC R 116.

As transistor 138 turns on, its collector current starts to flow throughresistor 136, causing a positive voltage to develop across it.Simultaneously the same voltage feeds through resistors 129 and 127 andcapacitor 128 to the base of transistor 130 to turn it on. The collectorand emitter provide a momentary ground path at the junction of 131 and132. This short circuit condition removes the current path which holdsSCR in the on state, SCR 116 switches off and subsequently turns offtransistors 138 and 137.

When transistor 137 is in an on state as described previously, itscollector current flows through resistors 139 and 141. A positive pulseis coupled by capacitor 140 and resistor 142 to the base of transistor143 to switch it on momentarily. The collector current of transistor 143flows through resistors 144 and 145 and develops a voltage across them.This voltage turns on transistor 146.

As transistor 146 is momentary in conduction, the collector-emittertransfers the positive voltage on terminal N to terminal in form of apositive pulse that is applied to the main chassis of the system or tothe chime operator. which subsequently activates all lights within thesystem.

Diode 124 is employed in the circuit to prevent a negative spike of thetransit pulse that might be destructive to the gate of SCR 116. Diode119 is used in the circuit to isolate the power supply source fromterminal N to the unfiltered DC voltage of the diode 111.

The system installation is generally shown in FIG. 6. The system isprovided with two photocells. One photocell is mounted on the exteriorof a building such as a garage to prevent the operation of the systemduring daylight hours. It is recommended to mount the exte riorphotocell on a shaded area to avoid direct sun and rain. The interiorphotocell is mounted within a garage at the same level as headlights, or20 /8 inches from the ground to detect headlights of cars for triggeringsystem when a car is parked in garage. In a two-car garage, the interiorphotocell may be centrally mounted between the two cars to detect eitheror both car headlights.

In some cases, such as in drive through carports, no wall is availablefor mounting of an interior photocell, a pneumatic switch may besubstituted for the interior photocell. A closed air hose supplies apulse of air to switch on the system as an automobile crosses the hose.A pair of wires connected between the pheumatic switch and TBl terminalsC and D of the main chassis are polarized so the switch won't operate ifwire is hooked up in wrong polarity.

The pneumatic switch is also useful for homes with driveways. Place thehose switch on driveway to alert the homeowner of approaching vehiclesby means of the door chime and lights.

Manual pushbutton switch for convenience should be installed near theentrance to garage and home. The chime operator box should be mountednext to the main chassis.

The wiring is indicated by the chime operator diagram in FIG. 6 asfollows. The push-to-light switch 16, normally connected to TB]terminals A and B of the main chassis, is connected to K and .1terminals of TB3 in the chime operator box. Jumper wires are connectedbetween terminals H, .l and K of T133 to terminals G, A and B of TB1. itis important to check for correct wiring because KB terminals of bothblocks are positive line and H-G terminals are grounded. A pair of wiresfrom terminal M and L is connected in parallel with the door chimebutton switch to provide chime operation.

The basic garage lights may be wired by licensed electrician to housepower lines using existing lamps in garage or passageway. This systemcan be wired into any garage light system without disturbing its normalelectrical function. Door lights and interior lights may replace oraugment garage lights.

Lights may be wired into the main chassis. An installer may mount themain box at a suitable place in the garage, run the l 17 volts AC lineto the nearest AC outlet, and connect all switch elements as described.

I claim:

1. A system for responding to intentionally indicated presence ofpersons comprising a power source,

a response means connected to the power source for receiving power fromthe source and performing a discernible response,

a controller connected to the source and to the response means forselectively completing a circuit from the source to the response means,whereby the response means operates,

a time delay means connected to the controller for delaying completeoperation of the response means,

intentionally activated indicator means connected to the controller forsetting the controller and time delay means in operation upon actuationof the in dicator means wherein the intentionally activated indicatormeans comprises an automobile presence sensing indicator means and adoorbell pushbutton switch mounted along side of a door, wherein theresponse means comprises door chime means, and wherein the controllercomprises a circuit connected between the indicator and the chime forringing a first tone of a chime and wherein the time delay meanscomprises an electronic time delay for delaying a ringing of a secondtone of a chime thereby to differentiate between indicator meansactivated by a doorbell pushbutton switch and by the automobile presencesensing indicator.

2. A system for responding to intentionally indicated presence ofpersons comprising a power source,

a door chime means connected to the power source for receiving powerfrom the source and performing a discernible response,

a controller circuit connected to the source and to the chime means forselectively completing a circuit from the source to the chime means,whereby the chime means operates,

a time delay means connected to the controller circuit for delayingcomplete operation of the controller circuit and an automobile presencesensing indicator means connected to the controller for setting thecontroller circuit and time delay means in operation upon actuation ofthe indicator means, wherein the controller comprises a circuitconnected between the indicator and the chime means for ringing a firsttone of a chime means and for delaying a ringing of a second tone of achime means thereby to differentiate between indicator means activatedby a doorbell pushbutton switch and by the automobile presence sensingindicator,

wherein the controller circuit further comprises a relay having normallyopen contacts and having a drive, wherein the door chime means iselectrically connected to the normally open contacts of a relay in thecontroller circuit, wherein the automobile presence sensing indicatormeans comprises electrical pulse generating means, and wherein thecontroller circuit further comprises gate means connected to the pulsegenerating means and transistor means controllably connected to the gatemeans, the transistor having a control terminal connected to the gatemeans and having power terminals completing a connection between therelay drive and the power source, and wherein the time delay meanscomprises charge storing means connected between the gate and thetransistor control terminal and discharging means connected to thecharge storing means for slowly discharging the charge storing means,whereby the indicator pulse generating means turns the transistor on,completing power to the relay and closing the contacts, supplying powerto the chime for a first tone, and whereby the generating meansconcurrently charges the storage means, which maintains powertransmission through the transistor, holding the contacts closed, andwhereby the discharging means causes the charge storing means to bedischarged and the transistor to be turned off after a delay, stoppingpower to the relay, permitting the relay contacts to open, andpermitting the chime to ring a second tone.

3. For the system of claim 2, wherein the controller means furthercomprises a circuit for lighting lights upon sensing presence of anautomobile, and wherein the intentionally activated indicator meansfurther comprises push-to-light switch means for activating the lightcontrolling circuit, and wherein the chime controlling circuit comprisesmeans for isolating the pushto-light switch means from operation of thechime, wherein the isolating means comprises a second transistor havingpower terminals connected between a base of the first relay powercontrolling transistor and ground, the second transistor having a baseconnected to the push-to-light switch means for biasing the secondtransistor on and grounding the base of the first transistor preventingon biasing of the first transistor upon pushing of the push-to-lightswitch means.

4. A system for responding to intentionally indicated presence ofpersons comprising a power source,

a response means connected to the power source for receiving power fromthe source and performing a discernible response,

a controller connected to the source and to the response means forselectively completing a circuit from the source to the response means,whereby the response means operates,

a time delay means connected to the controller for delaying completeoperation of the controller, and

intentionally activated indicator means connected to the controller forsetting the controller and time delay means in operation upon actuationof the indicator means,

wherein the controller includes a voltage divider circuit connectedbetween a power supply and a gate, wherein the intentionally activatedindicator means is connected on one side of the voltage divider forraising voltage level ofa midpoint in the divider circuit sufficientlyhigh to flow current through the gate, and wherein the voltage dividerfurther comprises deactivating means connected between the midpoint andground and receiving power from the gate for reducing voltage level ofthe midpoint sub sequent to gating of current and thereby deactivatingthe indicator.

5. The apparatus of claim 4, wherein the deactivating means comprisesfirst and second resistances serially connected from the gate to ground,and a storage device connected from a point between the resistances toground, whereby the storage device is charged by gated current, andfurther comprising a transistor having a base connected to the storagedevice for on biasing the transistor when the storage device issufficiently charged and wherein the transistor has power terminalsconnected between the midpoint and ground-for lowering voltage level ofthe midpoint upon on biasing of the transistor, and whereby thetransistor discharges through a resistance to reactivate the indicator.

6. The system for responding to intentionally indicated presence ofpersons comprising a power source, an intentionally activated indicatormeans comprising a doorbell pushbutton switch mounted near a door of ahouse and a response means comprising lights associated with the house,and a controller means comprising an electronic circuit connected to thepower source, to the pushbutton and to the lights and including a timedelay means for supplying power from the power source to lightsassociated with the house after a time delay which is consistent with anormal human response to a doorbell, whereby a person pressing adoorbell is aware of a normal human response to the ringing of thedoorbell.

7. The system of claim 6 wherein the doorbell pushbutton switch hasterminals connected to a chime and chime power source and wherein theterminals are connected through a diode and resistance to ground,wherein the resistance is connected between ground and a base ofa firsttransistor and wherein power terminals of the first transistor areconnected to a control terminal of a SCR switch, wherein the circuitfurther comprises a storage means connected to the power source forcharging the storage means and connected to control terminals ofelectronic switches for reversely biasing the switches off, and whereinthe SCR is connected to the storage device for slowly discharging thestorage device when the SCR is on whereby the electronic switches areturned on as the reverse bias charge drains from the storage means, andwherein the electronic switches further comprise power terminalsconnected to a light system for turning on the light system after thestorage means has been discharged sufficiently to permit turning on ofthe electronic switches.

8. The apparatus of claim 7 wherein the electronic switch meanscomprises a second transistor with power terminals connected forsupplying a pulse to a third transistor for momentarily switching thethird transistor on, and wherein the third transistor has powerterminals connected to a sensor input in an automatic light controlsystem for starting the automatic light control system after a timedelay during discharge of the storage means.

9. The apparatus of claim 7 further comprising a transistor having powerterminals connected between one power terminal of the SCR and ground forgrounding the SCR, and turning the SCR off, the transistor having a baseconnected to the electronic switch for turning on the transistor andgrounding the SCR when the electronic switch is turned on.

1. A system for responding to intentionally indicated presence ofpersons comprising a power source, a response means connected to thepower source for receiving power from the source and performing adiscernible response, a controller connected to the source and to theresponse means for selectively completing a circuit from the source tothe response means, whereby the response means operates, a time delaymeans connected to the controller for delaying complete operation of theresponse means, intentionally activated indicator means connected to thecontroller for setting the controller and time delay means in operationupon actuation of the indicator means wherein the intentionallyactivated indicator means comprises an automobile presence sensingindicator means and a doorbell pushbutton switch mounted along side of adoor, wherein the response means comprises door chime means, and whereinthe controller comprises a circuit connected between the indicator andthe chime for ringing a first tone of a chime and wherein the time delaymeans comprises an electronic time delay for delaying a ringing of asecond tone of a chime thereby to differentiate between indicator meansactivated by a doorbell pushbutton switch and by the automobile presencesensing indicator.
 2. A system for responding to intentionally indicatedpresence of persons comprising a power source, a door chime meansconnected to the power source for receiving power from the source andperforming a discernible response, a controller circuit connected to thesource and to the chime means for selectively completing a circuit fromthe source to the chime means, whereby the chime means operates, a timedelay means connected to the controller circuit for delaying completeoperation of the controller circuit and an automobile presence sensingindicator means connected to the controller for setting the controllercircuit and time delay means in operation upon actuation of theindicator means, wherein the controller comprises a circuit connectedbetween the indicator and the chime means for ringing a first tone of achime means and for delaying a ringing of a second tone of a chime meansthereby to differentiate between indicator means activated by a doorbellpushbutton switch and by the automobile presence sensing indicator,wherein the controller circuit further comprises a relay having normallyopen contacts and having a drive, wherein the door chime means iselectrically connected to the normally open contacts of a relay in thecontroller circuit, wherein the automobile presence sensing indicatormeans comprises electrical pulse generating means, and wherein thecontroller circuit further comprises gate means connected to the pulsegenerating means and transistor means controllably connected to the gatemeans, the transistor having a control terminal connected to the gatemeans and having power terminals completing a connection between therelay drive and the power source, and wherein the time delay meanscomprises charge storing means connected between the gate and thetransistor control terminal and discharging means connected to thecharge storing means for slowly discharging the charge storing means,whereby the indicator pulse generating means turns the transistor on,completing power to the relay and closing the contacts, supplying powerto the chime for a first tone, and whereby the generating meansconcurrently charges the storage means, which maintains powertransmission through the transistor, holding the contacts closed, andwhereby the discharging means causes the charge storing means to bedischarGed and the transistor to be turned off after a delay, stoppingpower to the relay, permitting the relay contacts to open, andpermitting the chime to ring a second tone.
 3. For the system of claim2, wherein the controller means further comprises a circuit for lightinglights upon sensing presence of an automobile, and wherein theintentionally activated indicator means further comprises push-to-lightswitch means for activating the light controlling circuit, and whereinthe chime controlling circuit comprises means for isolating thepush-to-light switch means from operation of the chime, wherein theisolating means comprises a second transistor having power terminalsconnected between a base of the first relay power controlling transistorand ground, the second transistor having a base connected to thepush-to-light switch means for biasing the second transistor on andgrounding the base of the first transistor preventing on biasing of thefirst transistor upon pushing of the push-to-light switch means.
 4. Asystem for responding to intentionally indicated presence of personscomprising a power source, a response means connected to the powersource for receiving power from the source and performing a discernibleresponse, a controller connected to the source and to the response meansfor selectively completing a circuit from the source to the responsemeans, whereby the response means operates, a time delay means connectedto the controller for delaying complete operation of the controller, andintentionally activated indicator means connected to the controller forsetting the controller and time delay means in operation upon actuationof the indicator means, wherein the controller includes a voltagedivider circuit connected between a power supply and a gate, wherein theintentionally activated indicator means is connected on one side of thevoltage divider for raising voltage level of a midpoint in the dividercircuit sufficiently high to flow current through the gate, and whereinthe voltage divider further comprises deactivating means connectedbetween the midpoint and ground and receiving power from the gate forreducing voltage level of the midpoint subsequent to gating of currentand thereby deactivating the indicator.
 5. The apparatus of claim 4,wherein the deactivating means comprises first and second resistancesserially connected from the gate to ground, and a storage deviceconnected from a point between the resistances to ground, whereby thestorage device is charged by gated current, and further comprising atransistor having a base connected to the storage device for on biasingthe transistor when the storage device is sufficiently charged andwherein the transistor has power terminals connected between themidpoint and ground for lowering voltage level of the midpoint upon onbiasing of the transistor, and whereby the transistor discharges througha resistance to reactivate the indicator.
 6. The system for respondingto intentionally indicated presence of persons comprising a powersource, an intentionally activated indicator means comprising a doorbellpushbutton switch mounted near a door of a house and a response meanscomprising lights associated with the house, and a controller meanscomprising an electronic circuit connected to the power source, to thepushbutton and to the lights and including a time delay means forsupplying power from the power source to lights associated with thehouse after a time delay which is consistent with a normal humanresponse to a doorbell, whereby a person pressing a doorbell is aware ofa normal human response to the ringing of the doorbell.
 7. The system ofclaim 6 wherein the doorbell pushbutton switch has terminals connectedto a chime and chime power source, and wherein the terminals areconnected through a diode and resistance to ground, wherein theresistance is connected between ground and a base of a first transistorand wherein power terminals of the firsT transistor are connected to acontrol terminal of a SCR switch, wherein the circuit further comprisesa storage means connected to the power source for charging the storagemeans and connected to control terminals of electronic switches forreversely biasing the switches off, and wherein the SCR is connected tothe storage device for slowly discharging the storage device when theSCR is on, whereby the electronic switches are turned on as the reversebias charge drains from the storage means, and wherein the electronicswitches further comprise power terminals connected to a light systemfor turning on the light system after the storage means has beendischarged sufficiently to permit turning on of the electronic switches.8. The apparatus of claim 7 wherein the electronic switch meanscomprises a second transistor with power terminals connected forsupplying a pulse to a third transistor for momentarily switching thethird transistor on, and wherein the third transistor has powerterminals connected to a sensor input in an automatic light controlsystem for starting the automatic light control system after a timedelay during discharge of the storage means.
 9. The apparatus of claim 7further comprising a transistor having power terminals connected betweenone power terminal of the SCR and ground for grounding the SCR, andturning the SCR off, the transistor having a base connected to theelectronic switch for turning on the transistor and grounding the SCRwhen the electronic switch is turned on.